An outer ring used in a bearing device for vehicle (hub unit) generally comprises a cylindrical main body comprising raceways in double rows in an inner peripheral surface thereof, a flange provided in an outer peripheral surface of the cylindrical main body, and a cylindrical fitting tolerance part on a vehicle inner side in comparison to the flange (see the Patent Document 1).
A knuckle is assembled to a side surface of the flange of the outer ring on the vehicle inner side and an outer peripheral surface of the cylindrical fitting tolerance part, and the outer ring is thereby assembled under irrotational state on a vehicle side. In the bearing device for vehicle thus constituted, it is necessary for the side surface of the flange on vehicle-inner-side and the outer peripheral surface of the cylindrical fitting tolerance part to be made finish machining with a required high precision.
A conventional method of manufacturing the bearing device for vehicle comprises a step of grinding the outer peripheral surface and inner peripheral surface of the cylindrical main body by holding the cylindrical fitting tolerance part of the outer ring using a holding device, a step of grinding the cylindrical fitting tolerance part by holding the outer peripheral surface of the cylindrical main body, a step of heat-processing the inner peripheral surface of the cylindrical main body and raceways, and a step of turning the cylindrical fitting tolerance part by holding the cylindrical main body as a finishing process.
Patent Document 1: No. 2001-315503 of the Japanese Patent Applications Laid-Open